Taking their cue from the Situationist's ideas of play as a means of engaging citizens, Haus-Rucker-Co created performances where viewers became participants and could influence their own environments, becoming more than just passive onlookers. These installations were usually made from pneumatic structures such as Oase No. 7 (1972), which was created for Documenta 5 in Kassel, Germany. An inflatable structure emerged from the façade of an existing building creating a space for relaxation and play..." via http://www.spatialagency.net/database/haus-rucker-co